Conventional automatic cleaning appliances, such as washing machines, dishwashers, and the like, involve the mixing of a wash aid with water to create a wash liquid to facilitate the cleaning process. These wash aids may include detergents, water softeners, fabric softeners, whitening agents, brightening agents, in-wash stain removers, color safe bleaches, peroxygen bleaches and the like. One dispensing method is for the appropriate quantity of wash aid to be added to the cleaning appliance by an operator prior to the initiation of the laundering cycle. The operator places the wash aid in a dispenser, and the wash aid is introduced into the water at a preselected step in the cleaning cycle. The effectiveness of the wash aid is dependent, at least in part, on the quantity of wash aid dispensed. Thus, accurate measuring and dispensing of the wash aid is very desirable.
Conventional cleaning appliances, such as washing machines and dishwashers, require a specific amount of detergent in order to optimize cleaning and minimize the generation of excess suds, which can be detrimental to the cleaning process and certain components, particularly pumps. High concentrations of detergent can also be damaging to certain fabrics. The quantity of detergent required will be dependent on the concentration of the detergent. Thus, for example, if too large a quantity of a high-concentration detergent is dispensed, excessive sudsing can occur, or fabrics can be damaged. Conversely, if too low a quantity of a low-concentration detergent is used, soil removal from the laundered items can be less effective.
The most common cause of incorrect concentrations is user error. Users have been known to fill the dispenser with too much or too little wash aid. As current dispensing systems flush all of the wash aid in the dispenser into the cleaning appliance, the amount of wash aid filled by the user will control the concentration of the wash liquid. Thus, the concentration of cleaning aid in the wash liquid or rinse liquid may vary considerably.